Tunnel field-effect transistors (TFETs) have been considered as a candidate to replace metal-oxide-semiconductor field-effect transistors (MOSFETs) in low-voltage, energy-efficient and ultra-scaled integrated circuits. By using quantum-mechanical tunneling instead of thermionic emission, TFETs have the potential to achieve switching slopes (SS) less than 60 mV/decade. In some applications, to compete favorably with MOSFETs, TFETs may be required to achieve an on-current (ION) approaching 1 mA/μm, a ratio of on-current to off-current (IOFF) greater than 105, and switching slopes less than 60 mV/decade. TFET devices using Indium arsenide (InAs) and Gallium antimonide (GaSb) as semiconductor materials have been demonstrated experimentally. InAs and GaSb exhibit narrow band gaps. Although these experimental devices have been shown to achieve a high ION, these experimental devices also show a large IOFF and as such, do not achieve an acceptable ION/IOFF ratio. Further, these experimental devices exhibit significant ambipolar conduction, due to the narrow band gaps, complicating circuit design with these devices. Thus, current TFETs, including those based on group III-V compounds exhibiting narrow band gaps, are less than ideal.